Current Situation and Future Development of UML

◇Department of Computer Science and Technology, Peking University Compile

 

UML It is a modeling language developed based on multiple object-oriented modeling methods and is mainly used for modeling software-intensive systems. Its evolution can be divided into the following stages by nature: the initial stage is the Joint Action of experts, composed of three Oo (Object-Oriented) Methodological scientists combine their respective methods to form Java 0.9 . The second stage is the joint action of the company, which consists of more than a dozen companies. UML Partner organizations "add their respective opinions UML , Forming Java 1.0 And 1.1 And act OMG Apply for a proposal to become a modeling language specification. The third stage is in OMG Revisions and improvements under control, OMG Yu 1997 Year 11 Formally adopted by month Java 1.1 As a modeling language specification, and then set up a task group for continuous revision, and produced Java 1.2 , 1.3 And 1.4 Version, where Java 1.3 Is an important revision. Currently in UML Major revision phase, with the goal of launching Java 2.0 , As direction ISO Standard proposal submitted.

In a situation where multiple object-oriented modeling methods coexist and compete with each other,UMLA unified flag is set up to enable system models developed by different vendors to present consistent model styles based on the same concept and using the same notation. In addition, it absorbs a large number of useful modeling concepts (or may be useful to some users) from multiple methods, so that its concepts and representations surpass any previous method in terms of scale, it also provides a mechanism that allows users to further expand the language.

UML UML it appears as a modeling language and is defined by some linguistic techniques. Although there are still many defects from the perspective of linguistics, its efforts in this area are incomparable to the previous modeling methods.

from UML , the computer industry has paid great attention to it. OMG the adoption of Unicode MS has put it in the real status of industrial standards with support from large companies, make it more and more users. It is widely used in application fields and various types of system modeling, such as management information systems, communication and control systems, embedded real-time systems, distributed systems, system software, etc. In recent years, it has also been applied to software re-engineering, quality management, process management, and configuration management. Moreover, its application is not only limited to computer software, but also can be used in non-software systems, such as hardware design, business processing processes, structures and behavior modeling of enterprises or institutions.

HoweverUMLWhile achieving great success, we are constantly criticized. Criticism from the industry is mainly because it is too large and complex, and it is difficult for users to master it comprehensively and skillfully. In fact, most users only use a small part of it; many of its concepts are unclear, making users confused. Criticism from academia focuses on its theoretical defects and errors, including the language architecture, syntax, and semantics.

At present, many software enterprises in China are learning and trying to use UML . In general, China's computer industry UML But its worship is far greater than that of Western developed countries. People are learning and using UML I am not very skeptical about the same problems and confusions as foreign users. UML What's the problem. Therefore, there is almost no criticism in China, and occasionally, it will be immediately drowned by the voice of defense, even if UML The same is true for some of the most obvious shortcomings and errors.

In contrast UML Is much more objective. Whether it is Internet Or once a year. UML The seminar was published in academic journals.ArticleBoth affirmed their achievements, pointed out their shortcomings and errors, and put forward constructive comments with a positive attitude. Brewing UML Next major release and planning Java 2.0 As ISO Within the last two years of the standard proposal UML The discussion is more active and enthusiastic.

In order to make China's computer industryUMLWe have a more objective understanding of the current situation. We have selected three most authoritative articles from a large number of documents to introduce them to readers in China. From this group of articles, we can get information aboutUMLStatus Quo and important information for future development:

●UMLIt has been an important success. It has become a dominant modeling language in the software industry and has been applied in software development in many fields.

● UML There are still many problems that have never left criticism since the very beginning: Users and teachers complain that the content is huge, hard to learn, difficult to teach, and too complex. ; Scholars believe that it lacks a refined core and well-defined perimeter. Some semantics are not accurate enough and have ambiguity. ; Modeling practitioners believe that it lacks a mechanism to support their own domain modeling requirements ; Tool developers are biased in understanding due to the uncertainty of the Specification. UML May mislead users.

●UMLThe key issue is too large and complex, as well as theoretical defects in the language architecture and semantics. One of the important reasons for these problems is that, in the process of standardized formation, we have to take care of the viewpoint of multiple approaches and the interests of multiple companies.

● To UML Next major release, Java 2.0 The author of the amendment is extensively collecting comments from various parties. People from all walks of life have paid great attention and the Comments involved UML . One of the key issues is UML Whether to simplify it or how to make it more refined. In the end, most of the opinions are to provide a refined core, and put the less commonly used content into a well-defined peripheral or extended mechanism. In addition, Java 2.0 Also UML The underlying structure, upper structure, and object constraint language ( OCL .

originally UML 2.0 released some time this year, however, in the current year, UML no news about the latest version progress was disclosed at the international seminar, it seems that its launch is more than expected.